Magnetic traction-wheel drive.



A. SUNDH. MAGNETIC TRACTION WHEEL DRIVE. APPLICATION FILED DEO.16, 1905.

2 8HEBTS-SHEET 1.

INVENTOR I M BY 77am 6% J I TTORNEY A. SUNDH.

ACTION WHEELDRIVE.

DEG. 16

Patented Nov. 1, 1910.

2 SHEETS-SHBET 2.

MAG

imirnn STATES grnnr OFFICE.

AUGUST SUN'DH, or YONKERS, NEW YORK, ASSIGNOR 'ro'orrs ELEVATOR COMPANY, or JERSEY CITY. new JERSEY, a oonronnrron or NEW JERSEY.

MAGNETIC TRACTION-WHEEL DRIVE.

Specification of Letters Patent.

await.

Patented Nov. 1, 1918.

Application filed December 16, 1905. Serial No. 291,936.

city of Yonkers, in the county of est-- chester and State of New York, have invented a new and useful Improvement in Magnetic 'lraction-ll'heel Drives, of which the following is a specification.

My invention relates to traction elevator systoi'ns. and one of its objects is the provision of simple and etticient magnetic trac' tion driving apparatus.

Another object of my invention is to provide a magnetic traction wheel drive combined with means for automatically magnet.- izing substantially only that portion of the wheel that is in engagement with the hoisting cable or cables.

Other objects of the present invention will appear hereinafter, the novel combinations of elements being pointed out in the claims.

In the accon'ipanying drawings, Figure 1 represents more or less diagrami'natically an electric elevator system illustrating the application of my invention; Fig. 2 illustrates a side view, partly in section, of the magnetic traction driving sheave; and Fig. 3 is a plan view thereof, also partly in section:

Fig. t represents diagrammatically the windings and connections for effecting the i'nagi'ietization of a predetermined portion of said sheave; and l igio is a detail view of the brake mephanism carried by the car.

Referring particularly to Fig. 1, it will be observed that the elevator car C is provided with the usual guide shoes 1, 1. at the upper portion thereof and is adapted to be moved'u and down in an elevator well by means 0 the driving apparatus comprising the motor M and the magnetic traction sheave T. G, G designate the guide rails, D the brake mechanism secured to the bottom of the car, S an electric switch in the car-and 2 the hoisting ropes which pass'over the sheaves 3, 3' mounted on the overhead beam 4., and thence downwardly to the traction sheave T and upwardly to the counterweight sheave 5 and counterweight W.

The sheave 5 is shown mounted-on an additional overhead beam 4 which may be in the .same horizontal plane with the beam t, or the sheaves 3- and 5 may be on opposite sides of the beam 4. The counterweight is adapted to move over suitable stationary guides and is provided with brake mechanism which is shown in this instance as similar to that mounted on the bottom of the car.

The motor M is mounted on a bed-plate 6 which is shown as supporting also the brake B adapted to be applied to the brake pulley P. The traction sheave or wheel T is fixed to the motor shaft 7 so that when the motor is operated the car will be hoisted or lowered depending upon the previous operation of the controlling apparatus.

In Fig. 5, I have shown in detail a brake for the car and counterweight, although any other suitable brake could be used, that here shown being merely for the sake of illustration. Clamps 9, 9 are arranged to be actuated by the springs 10, 10 to grip the guides and stop the'car. These springs encircle extensions 12, 12 of the magnet cores 12, 12 between the collars 11,11fiited to said extensions and the magnet casing 14. The rods 12, 1.2 are connected to the clamps and are adapted to move in suitable bearings 13, 13. ,Normally the clamps grip the guides, but: when the magnet solenoid 15 is excited with electric current the clamps are released and the car may be moved.

The motor-controlling apparatus com prises reversing switches R. R, preferably mounted on thecontroller board near the motor, a manual switch S in the C81,2\CCGlerating apparatus A. and the brake B. \Vhen the lever 99 is moved onto the contact 16 and the main line switch L is closed acircu'it will be closed through the solenoid 20 to operatethe reversing'switch R. This circuit may be traced from the positive main through wires 18 and 19 to and through solenoid 20', wire 21, contact 16, lever 99,

wires 22, 23 and 24 to the negative main. The switch R will thereupon be closed and.

the motor circuit will then be completed negative main; The shunt field circuit: will beolosed by'the auxiliary switch .X, the circuit' being from the )ositivemain bywayuof .=Wire 18,, contact 38, ridge iece 39, contact 40, wire 41, motor termina t2, shunt field circuit (not shown), motor terminal 13,

. wires Hand 24 to the negative main.

It should be noted that when the armature circuit is closed by the reversing switch R. a circuit is closed in shunt to the armature from the point by wire 46, through the magnet solenoid 15 of the brake apparatus attached to the car. and thence by wire 47 through the magnet solenoid 15 of the counterweight brake-mechanism; from here the circuit continues by way of wire 48 through the motor brake magnet 49 and wires 50 to the terminal 51 of the traction wheel circuit position, the car brake, counterweight brake and motor brake will be released and the motor may start at a slow speed since the currentfed to the same is limited by the starting resistance 8.

Any well-known means for gradually short-circuiting this resistance may be used for accelerating the motor to full speed. I have in'this instance shown by way of illustration a plurality of electromagnets ar ranged in series in a circuit in effect connected across the armaturebetween the points 45 and 55. Adjustable stop screws 56 in a fixed piece 57 limit the downward movement of the magnet cores which carry at their upper ends contact-makers 58 for bridging the contacts 59 connected to the resistance 8 at various points. It w'lltbe 'seen that these bridging pieces are at ifferent distances from the fixed contacts 59 so that as the counter-electro-motive force of the armature gradually builds up the current through the accelerating magnets gradually increases in strength and the magnets therefore fly up one after another to suecessively close their switches and step-by step short-circuit the resistance 8.

By reference to Figs. 2 and 3 it will be seen that the wheel '1 1s in reality a multipolar electromagnet, its poles (B-t being ra dial and each provided with a winding or coil of insulated wire. Said wheel or sheave comprises a hub (30, web (31 and run (32. The

hub is suitably secured to the motor-shaft 7. The web may be replaced by spokes and the construction of the sheave otherwise varied as desired so long as it .is of requisite strength andcomposed of material that is easily magnetized'and (lo-magnetized by electric current passing through solenoids which encircle the. poles. The wheel may be cast solid and slots (35 cut in afterward to form any desired number of poles or said slots may be formed by the mold itself in casting. Furtheremore, if desired, the poles may be made removable in which case they could be easily replaced if injured or the hub-and-web portion'could be constructed of different material. The slots are herein shown at substantially right angles to the plane of the sheave T but I do notdesire to be restricted to this exact construction as the slots may be arranged diagonally. Grooves 67 are also formed in the peri )hery of the wheel in any desired manner and rims (36, (36 provided to prevent the hoisting ropes from being easily thrown off. In order to make a solid wheel of increased strength-the slots may be filled with nonmagnetic material.-

One or more hoistingropes may be used. I have herein shown four, but since they move together they may be considered'as separate strands of a single rope if desired. Of course it is necessary in order to accomplish some of the objects of. this invention that the hoisting rope be of some magnetic material and it is preferable that this material be such as will lose its magnetismverv easily though this particular feature is not essential.

It may be explained that the principle of my invention is based on the fact that if the frictional contactbet-wcen the hoisting ropes and the driving pulley, sheave or wheel '1 is increased the tendency of said wheel to slip on the ropes is very much diminished. Furthermore, more power can be efiiciently, exerted in operating a car heavily loaded as the traction drive may be increased without causing any slipping. For instance, if the load in the car is very heavy and the brakes are all released the car might be moved downwardly by reason of excessive underbalanced load. The hoisting ropes would therefore slip but to allow such a load to be safely moved up or down. I increase the traction effect of the wheel '1 by transforming the same into a multipolar electro-magnet. If desired the driving sheave may he composed of one or more permanent magnets insteati of electro-maguets.

Itis evident that the weight of the car and load acting 011 one end of the hoisting ropes and the weight of the counterweight acting on the other end thereof will e'liect a frictional engagement of the ropes with sub stantially half of the periphery of the driving sheave T, but this alone andwithout any intermediate friction producing sheaves would ordinarily not be suflicient. To eliminate such intermediaries and thus decrease the wear on the ropes .due to bending. I magnetize the sheave preferably with electrie current actin on electro-magn ets, which in turn attract tie ropes into firmer frietional engagement with the driving sheave.

' In this instance I have shown a small s11 it should be noted that if all thcpoles of this magnet were energized the hoisting rope would tend to be drawn out. of vertical alinement as shown at 2' in Fig.2 in dotted lines, thus putting a wearing strain on the rope and also uni-iecessarily retarding the movement thereof. To overcome this ditticulty I provide a con'miutating arrangement so that each electro-inagnet is deenergized when the rope is about to move out of engagement with its pole, as shown, for example, in the lower part of Fig. 2; and again energized when it'returns into engagement substantially throughout its whole length with said rope as shown at the upper side of Fig. 2.

port (39 (Fig. 1) secured to one of the motor shaft bearings 71 mounted on the standard.

70. Secured to the upper endof the support (39 is an insulated spring pressed brush T2 in sliding engagement with the slip ring 73 secured to but insulated from the web 61 of the wheel T.

Intermediate the. brush 72 and the bearing 71 is connected a bar or rod constituting the terminal 51. On the inner end of this rod is fastened or pivoted the brush' holder 74 carrying a plurality of brushes 75 electrically connected to each other and bearing on the segments 76 of the commutator connects ed to the hub 0 of the wheel T. If desired, the brush holder support ()9 may be rotatably mounted so that the brushes could beshitted to various positions depending upon the position of the traction wheel T with respect to the overhead sheaves 3' and 7;. that whether directly under the latter or to one side or even above if the hoisting apparatus is placed at the top of the ele 'ator well. Furthermore, the length of the brush holder maybe'increased or decreased so as to engage a greater or less number of segments in order to effect the cnergization of a predetermined number of coils 78 at one time. The brushes 75 may be separately mounted in the brush holder 7-1 at equal distances or irregularly but since they are electrically connected together these brushes could be replaced by a single are shaped brush of the requisite length, if desired.

The separate brushes are preferable, however, as they pcrnnt better adpistmcnt and can be easily replaced when worn out;

When the parts are in the position shown in Fig. 4 the current may enter at the ter minal BI and pass by way of brush-holder 74- and brushes 75 to several of the segments of the commutator and thence through the magnet coils which are preferably so arranged that the poles are alternately of north and south polarity. "By the addition of another brush, coil 88 could also be ex-.

cited or the brush holder could be shifted so thatcoil 88 would be energized and coil 87 deenergized. The coils on the lower side of tens Patent of the Unite d StatesIis': v

the wheel are thus C(H lllttflefilll] pa ralle.l\vi'til1 'each other, 79 designating the common return connection to the main. It isev'ident that as the wheel revolv "andthecommw tator segments pass under "and awayiifrom 7 y the brushes only a predetermined number of coils a re maintained energized'and the parts" may be so constructed and arranged that each magnet will be energized whenfits face is in engagement throughoutiit's lengt-li with 75 theropes 2 and eachupwardly-moving magnet will be deeuergiz'ed-astherope :is'aboutfi" to leave said face, but obviously any other adjustment. may be made. {Itfinay in some instances be found desirable to energize: a 50 particular pole while "the-ro ne is in contact with a portion of its face. "hisis "SllOWlljlll- Fig. i where, assuming that'the car is being lifted and consequentlythewheel' T rotating in a clockwise direction. th'e coil 89-.is aboutas to be energized, the 'coil'78 about to be deenergized, and coil SS'is already deenergized.

By adding another brush coil 88*could be kept energized 'fOl adltt'ltx longertime=so that diametricallyopposite 'coils,as 90 and 9c 87, could be deener'gized-j and energized" re-- spectively at substantially a sume, time.

In the position shown in Fig. 2"coil 90 should have already been-deiinergizedand coil 86, or both coils 86 and-87, energized.

I .Without limiting-thyselfto *theuprecise construction of"'details or arrangement. of parts herein. shown and described, what I claim and desire-to haveprotected. by-Let- 1. In a traction elevator, the, combination with a car, and counterweight, of brake apparatus for said our and counterweight, hoisting cables connecting said car and counterweight, a magnetic sheave associated with said cables, a motor for driving said sheave,'and means for simultaneously energizing said sheave and releasing said brake apparatus.

2. In a traction elevator, the combination with a car, of electromechanical brake apimore cables-connectingthecar and ooun'terweight, a magnetic traction sheave, windings for said sheave, a motor for driv ng said sheave, and means operable from the car for simultaneously energlzin said brake-mag net, sheave windings, an motor.

4. In a traction elevator, the combination 'said electric releasing means and electrowith a car, counterweight and Cat l'es, of brake apparatus for the'car'and' counterweight, electric releasing means for ,said brake apparatus, an electro-magnetic traction sheave associated with said cables, means, controllable from the car for operating said electric-releasing means and effecting the energization of said traction sheave, and a motor for driving said sheave.

5. In a traction-elevator, the combination 1 with a car, counterweight and cables, of brake apparatusfor the car, electric releasing means for said brake apparatus, an electro-' magnetic traction sheave, a motor for driving said sheave, reversing switches for the motor controllable from the car, and connections between said reversing switches and magnetic traction sheave to effect the operation of'the releasing means and the energizetion of said traction sheave when either reversing switch is closed.

6. In a traction elevator, the combination with a car, counterweight and cables, of brake apparatus for the counterweight, electrio-releasing means for said brake apparatus, an electro-magnetic traction sheave associated with said cables, means controllable from the car .for operating said electric-releasing-means -and effecting the energization of said traction sheave, and a motor for driving said sheave.

7. In a traction elevator, the combination with a car, counterweight and cable, of a traction sheave, a motor, meansfor supplyingpower to the motor, and electromagnetic means for automatically increasing the traction between the cable and sheave when power is supplied to the motor, and decreaspower is cut oil from drivin'gthe sheave, an electromagnetic device for increasing the tractionbetween the sheave and rope or cable, means for controlling the brake, and means for controlling said device to increase the traction between the sheave and rope or cable when the brake is released, and decrease the traction when the brake is applied.

9. In a traction elevator, the combination with'a car, of an electro-magnetic sheave, a

motor arranged to dr1ve said sheave, and means for varying the magnetism of said sheave in proportion to the speed of the.

motor.

-10. In a traction elevator, the combination of an. electro-magnetic sheave, and means for automatically varying a resistance in circuit with the windings of said sheave.

11. In a traction elevator, the combination of an electric motor, an electro-magnetic sheave connected to said motor, and means for varying a resistance in circuit with the windings of said sheave in )roportion to the connter-electro-motiveorce of said motor. I

lg testimony whereof, I have signed my name to this specification in the presence of two subscribing witnesses.

AUGUST SUNDH.

Vitnesses CHARLES M h ssniv,

AXEL MAGRUESEN. 

